<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>client</title>
    <style>
        .container{
            width: 300px;
            height: 400px;
            margin: 0 auto;
            border: 3px solid black;
        }
    </style>
</head>
<body>
    <div class="container" id="container">
    </div>
    <script>
        const container = document.getElementById("container")
        console.log("offsetHeight",container.offsetHeight)
        console.log("clientHeight",container.clientHeight)
    </script>
</body>
</html>